• Fisheries and Aquatic Sciences
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• 제14권4호
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• pp.379-388
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• 2011

The mechanism by which gonadotropin-releasing hormone (GnRH) and dopamine (DA) control gonadotropin (GTH) release was studied in male and female rainbow trout using cultured pituitary cells obtained at different reproductive stages. The mechanisms of follicle-stimulating hormone (FSH) release by GnRH and DA could not be determined yet. However, basal and salmon-type GnRH (sGnRH)- or chicken-II-type GnRH (cGnRH-II)- induced luteinizing hormone (LH) release increased with gonadal maturation in both sexes. LH release activity was higher after sGnRH stimulation than cGnRH-II stimulation at maturing stages in both sexes. The GnRH antagonist ([Ac-3, 4-dehydro-$Pro^1$, D-p-F-$Phe^2$, D-$Trp^{3,6}$] GnRH) suppressed LH release by sGnRH stimulation in a dose-dependent manner, although the effect was weak in maturing fish. The role of DA as a GTH-release inhibitory factor differs during the reproductive cycle: the inhibition of sGnRH-stimulated LH release by DA was stronger in immature fish than in maturing, ovulating, or spermiated fish. DA did not completely inhibit sGnRH-stimulated LH release, and DA alone did not alter basal LH release. Relatively high doses ($10^{-6}$ or $10^{-5}M$) of domperidone (DOM, a DA D2 antagonist) increased LH release, which did not change with reproductive stage in either sex. The potency of DOM to enhance sGnRH-stimulated LH release was higher in maturing and ovulated fish than in immature fish. These data suggest that LH release from the pituitary gland is controlled by dual neuroendocrine mechanisms by GnRH and DA in rainbow trout, as has been reported in other teleosts. The mechanism of control of FSH release, however, remains unknown.

• Journal of Korean Neurosurgical Society
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• 제41권6호
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• pp.367-370
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• 2007

Objective: Pituitary adenomas are common neurological lesions believed to account for 10% to 15% of all primary brain tumors. There can be diagnostic confusion due to discordance of the preoperative endocrine and the postoperative immunohistochemical diagnosis. In this study, the rate of discordance between preoperative and postoperative findings and their clinical implications were investigated. Methods: From March 2005 to March 2006, 26 patients who underwent surgery for a pituitary adenoma were enrolled in this study. The preoperative pituitary hormone level and postoperative immunohistochemical results were compared and analyzed. Results: The median age of the patients was 38 years [range 15-66 years]. The male to female ratio was 8 to 18. The endocrine evaluation showed 16 hormonally-active and 10 hormonally-inactive adenomas. The immunohistochemical findings showed : 13 prolactin-positive, 1 GH-positive, 1 FSH-positive, 8 pleurihormone-positive and 3 stain-negative adenomas. The percentage of discordance observed between the preoperative endocrine and postoperative immunohistochemical diagnosis was 54%. Nine of 10 endocrine non-functioning adenomas showed : 3 PRL positive, 1 GH positive, 2 PRL+GH positive, 1 TSH+FSH positive, 1 FSH+ACTH+PRL positive and 1 FSH+LH+PRL positive adenomas by immunohistochemistry. Three endocrine PRL+GH secreting adenomas showed 2 PRL positive and 1 FSH+GH positive by immunohistochemistry. One endocrine PRL secreting and 1 GH secreting adenoma showed 1 PRL+ TSH positive and 1 GH+PRL positive by immunohistochemistry, respectively. The diagnosis of the other 12 pituitary adenomas showed concordance. Conclusion : The results of this study showed 54% discordance rate between the preoperative endocrine and postoperative immunohistochemical diagnosis for pituitary adenomas.

• 한국발생생물학회지:발생과생식
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• 제28권3호
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• pp.75-86
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• 2024

Artificial sexual maturation of eel (Anguilla japonica) involves rearing in seawater and injecting salmon pituitary extract (SPE). The salinity of seawater and components of SPE influence hormonal activities of the eel pituitary, leading to gonad development. This study investigated the direct effects of salinity change and SPE treatment on the eel pituitary gland using primary cell cultures. Pituitary cells were cultured into four experimental groups: control culture (control), SPE-treated culture (SPE), NaCl-treated culture (NaCl) and NaCl+SPE NaCl+SPE treated culture (NaCl+SPE). We investigated the expression of genes presumably related to reproduction and/or salinity, including luteinizing hormone (LHβ), follicle stimulating hormone (FSHβ), progesterone receptor-like (pgrl), prolactin (PRL), dopamine receptor D4 (drd4), neuropeptide B/W receptor 2 (NPBWR2) and relaxin family peptide receptor 3-2b (rxfp3-2b). Gene expression analysis revealed significant upregulation of LHβ in SPE and NaCl+SPENaCl+SPE groups compared to control and NaCl (p<0.05). FSHβ expression did not show any significant changes. PRL showed a significant decrease in the NaCl group (p<0.05). Pgrl, NPBWR2, drd4, and rxfp3-2b displayed the highest expression in the control group, with downregulation observed in all treatment groups (NaCl, SPE, and NaCl+SPE) (p<0.05). This study demonstrated the direct effects of salinity changes and SPE treatment on the eel pituitary. Results from this study also suggest that salinity change is necessary but work together with SPE to induce reproductive process, and that LHβ, pgrl, PRL, drd4, NPBWR2, and rxfp3-2b genes are obviously associated with reproduction and salinity changes in eels.

• Journal of Korean Neurosurgical Society
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• 제45권5호
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• pp.271-274
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• 2009

Objective: We retrospectively analyzed the surgical outcomes of 42 patients with growth hormone (GH)-secreting pituitary adenoma to evaluate the clinical manifestations and to determine which preoperative factors that significantly influence the remission. Methods: Forty-two patients with GH-secreting pituitary adenoma underwent transsphenoidal surgery (TSS) between 1995 and 2007. The patient group included 23 women and 19 men, with a mean age of 40.2 (range 13-61) years, and a mean follow-up duration of 49.4 (range 3-178) months after the operation. For comparable radiological criteria, we classified parasellar growth into five grades according to the Knosp classification. We analyzed the surgical results of the patients according to the most recent stringent criteria for cure. Results: The overall rate of endocrinological remission in the group of 42 patients after primary TSS was 64% (26 of 42). The remission rate was 67% (8 of 12) for microadenoma and 60% (18 of 30) for macroadenoma. The remission rate was 30%(3 of 10) for the group with cavernous sinus invasion and 72% (23 of 32) for the group with intact cavernous sinus. Cavernous sinus invasion in Knosp grade III and IV was significantly correlated with the remission rate. There was a significant relationship between preoperative mean GH concentration and early postoperative outcome, with most patients in remission having a lower preoperative GH concentration. Conclusion: TSS is thought to be an effective primary treatment for GH-secreting pituitary adenomas according to the most recent criteria of cure. Because the remission rate in cases with cavernous sinus invasion is very low, early detection of the tumor before it extends into the cavernous sinus and a long-term endocrinological and radiological follow-up are necessary in order to improve the remission rate of acromegaly.

• 한국동물학회지
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• 제37권3호
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• pp.377-384
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• 1994

The present study examines the inhibitow effect of progesterone (P) on luteinizing hormone $(LH)\beta$ subunit gene expression in anterior pituitary of ovariectomized, estradiol-treated adult rats. A single injection of P (1mg) further decreased the estradiol-Induced decrease in $LH\beta$ mRNA levels in ovariectomTzed rats in a time-dependent manner. p suppressed UIP mRNA levels at lower doses (0.1 and 1mg), but increased $LH\beta$ mRNA levels 81 a high dose (toms). The inhibitor action of P on $Uf\beta$ mRNA was restored when Ru486, a P receptor antagonist, was administered 1h before P treatment. These data clearly indicate that P inhibits gene expression of $LH\beta$ in the rift pituitary in a swersic manner with estrogen.

• Fisheries and Aquatic Sciences
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• 제1권1호
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• pp.19-23
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• 1998

Effects of pituitary and thyroid hormones on estradiol-induced vitellogenin (VTG) induction were electrophoretically examined in primary hepatocyte cultures of rainbow trout. Hepatocytes were precultured for 2 days and then estradiol-17 $\beta$ $(E_2,\;2 \times 10^{-6}M)$>, triiodothyronine $(T_3,\;10^{-8}-10^{-6}M)$, bovine growth hormone (bGH, 10-100 ng/ml), ovine prolactin (oPRL, 100-500 ng/ml), and pituitary extract (PE) of rainbow trout (0.75PE/dish) were added to the incubation medium. The hepatocytes were cultured for 7 more days. The addition of oPRL to the incubation medium was not effective in increasing VTG production at any concentrations. The addition of PE to the incubation medium with $E_2$ was not effective in increasing VTG production. The addition of bGH to the incubation medium with $E_2$ was not effective in increasing the rate of VTG production at concentrations of 10-50 ng/ml. However, a higher concentration of bGH, 100 ng/ml, increased VTG production. The various concentrations of $T_3$ were ineffective in stimulating VTG production. These results suggest that GH could be one of stimulus factors for VTG production in rainbow trout.

• 한국발생생물학회지:발생과생식
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• 제12권1호
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• pp.97-105
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• 2008

Vinclozolin (VCZ)은 침투성 살균제로써 과일, 채소, 와인산업에 널리 사용된다. VCZ와 그것의 대사산물들인 butenoic acid (M1)과 enanilide (M2)는 안드로겐 수용체를 놓고 항 안드로겐 물질로 작용한다. VCZ가 수컷의 생식생리와 병리에서 내분비계 장애물질(endocrine disrupting chemical, EDC)로 작용함에 대한 증거는 많이 있지만, 암컷 생식생리에 미치는 VCZ의 효과에 대한 증거는 전무하다. 본 연구자들은 이전 연구에서 VCZ가 미성숙 암컷 흰쥐의 사춘기 개시를 유의하게 지연시킴을 보고한 바 있는데, 이는 VCZ에 의해 시상하부-뇌하수체-난소(hypothalamus-pituitary-ovary, H-P-O) 생식 호르몬 축의 활성이 지연되거나 약화됨을 시사한다. 본 연구에서는 미성숙 암컷 흰쥐들의 VCZ 투여가 암컷 흰쥐의 시상하부-뇌하수체 축의 생식 호르몬 관련 유전자들 활성에 미치는 영향을 조사하였다. VCZ (10 mg/kg/day)를 생후 21일부터 첫 번째 질구개방이 관찰되는 날까지 매일 복강주사하였다. 시상하부와 뇌하수체의 표적 유전자들의 전사적인 변화량을 측정하기 위하여, total RNA를 추출하였고 반 정량적 역전사 중합효소반응(RT-PCR)을 실시하였다. VCZ 투여군에서 시상하부의 gonadotropin-releasing hormone (GnRH)의 분비를 조절함이 알려진 nitric oxide synthase-2 (NOS-2)의 전사활성은 대조군보다 유의하게 감소하였다(p<0.01). 유사하게, VCZ 투여군의 시상하부에서의 KiSS-1, G protein-coupled receptor54 (GPR54) 그리고 GnRH mRNA 수준도 감소하였다(p<0.01). 예상대로, VCZ 투여군의 뇌하수체 luteinizing hormone-${\beta}$ (LH-${\beta}$)과 follicle stimulating hormone-${\beta}$ (FSH-${\beta}$) 전사활성도 대조군에 비하여 유의하게 감소하였다(p<0.01). 이번 연구를 통해 미성숙 암컷 흰쥐의 VCZ 노출시 사춘기 개시의 지연효과는 시상하부-뇌하수체 신경내분비 축의 GnRH와 KiSS-1같은 성선자극호르몬들과 그들의 상위조절인자들의 전사 활성의 감소에 의해 야기되고, 아마도 nitric oxide (NO) 신호전달경로에 의해 조절됨을 시사한다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.178.1-178
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• 1999

No Abstract, See Full Text

• 한국동물학회:학술대회논문집
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• 한국동물학회 1997년도 한국생물과학협회 학술발표대회
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• pp.197.2-197
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• 1997

No Abstract, See Full Text

• BMB Reports
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• 제42권4호
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• pp.206-211
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• 2009

Proopiomelanocortin (POMC) plays an essential role in the stress response of the hypothalamic-pituitary-adrenal axis, and is the precursor of biologically active peptides such as adrenocorticotropin (ACTH), $\alpha$-melanocyte-stimulating hormone ($\alpha$-MSH), $\beta$-melanocyte-stimulation hormone ($\beta$-MSH) and $\beta$-endorphin. We have synthesized two different forms of POMC cDNA clones, POMC-I and POMC-II, from a pituitary cDNA library for Paralichthys olivaceus, or Japanese flounder. jfPOMC-I cDNA consists of 954bp and encodes a polypeptide of 216 amino acid residues, whereas jfPOMC-II consists of 971bp which encode a polypeptide of 194 amino acid residues. The high levels of jfPOMC-I and -II mRNAs detected in the pituitary tissue and moderate levels detected in the brain tissue plus our quantitative RT-PCR analysis, which showed there to be no significant difference between the levels of jfPOMC-I and -II mRNAs, indicate that there may be no functional separation between these two mRNAs in the flounder.